Internal-combustion engine



April 7, 1931. L. M. wooLsdu 1,799,271

INTERNAL COMBUSTION ENGINE 7 Filed July '7. 1926 Patented Apr. 7, 1931 COMPANY, OF; .IDETRQI'I, Ii/PIG'III,Gr'AN,v A CORPORATION OF MICHIGAN xiwiaiamncomesiirbfi 4 A piiesti sn filed {Imi 7, 192%. semivb. {121,004.

systems for internal combustion. engines.

"In iubricatihg' en ines, partic ulsrly engines Operating atdnghs eds su h asairplane en iiiesdt is desirable te previde lubri- *c'a11t circ'tflatmg systems 'iriclurling a, sfiitztble source of suppl en'rieeted witirthe meek-ianism to'fheghihiifzsltd by 'maii's "of-suitable conduits, a feed {pump io'ifmillyf interposed in said cbnduits'hetweeh-the supply tank end the engine t6 pesitiv'ely 'feed hibrieafit 'tethe latter, and a "disehargepumpinteiiposed between theeng'ine ah'dthe sup-ply'mnkfor-returning'lfibficant t0 the lfatter. Usuall the discharge pump has gleatercap aci-ty thanthe vide a relief v-alife connectedtb thefieed line and to the engine, W'hidhfizilve is adapted to open when the pressurereaehe's a pied'etermined amofintmi-d m llow zypartio'f thehibri- .caiit to escape tethe crank-case; "With-shell system, the cape-city of the discharge-pump must else he great'ehoiigh tewithc'lra'w this additional ameimt Ofj llibfiea'nt whieh has served no system;

useful purpose in the lubrication Moreover, the "-supply -tzihk is mushy of necessity connected with Fth "feed and discharge pumpshy co-ridilitisbf some length, 111

which theliibricantrapidly congeals in 1 eeld Weather when the engine-is Stop ed, When the engineis' started 'clcLthe feetl pump "delivers very little lubricant 1:0 the'engine' 'he- Cause oft-his cenditien of the oilfin, the 001 1 duit s, uhti1- the system is warmed up,;and

Warming up'is delayed'by the lack of airculation ofthe, lubrieari-t; Ithasheeh feuiid the 'diseharge piimpafefi en though 1t-1s partly congealed, and because (if the ihoreor ls's .qfi' eamdsm of the "lubricant iii e the eonjdiiit amtheoutlet side Of this pump a high p1 essure"there*bui1t up;

wLIONEL miwoo soirgonf Disraeli, YVMIVQHIGAN; es mi qg mo iAOKARD MOTOR een OneObjeQt of thisin'venfiio is to profile a liibsi atingsys'tem whiehwilleliminatethe ebov disadvamyages' and will insure'fiprdper sa pl if lubriea t-Jto the mechanism to "he lubricated."

:Anether (abject is'toprevidemeans-ivhere- "it-fu ther 'o'bjeetisto provide means tor 1 igposltwely =feec1ing lubricant meme-mecha- J nism' whee the engine 'sta'Tted 60161.

A still further object is to prdtide means ii hereby the lubricant in the emhk ease may "be e'tnpl-oy ed to; 111bricste the mechanism when the: feed from "the-suppl ttifik is insufficient.

Anether object *is to provitle mesh-s whie- 1 by the discharge pump will be mitomatical- 1y connected with themeh'anism m be lube Gated sneer term conditions of opefiation, to thereby deliver' lfibr icant to said mecha- -n'i'srh; i

-O*i1eeh 1hpdimeiit 6f the invention is illust'iat'ed in the accompanying drawingsgbub #ihseflmwihgs are for ur qses 0f ilhist-rati-i611 otily endare-netto be taken' as defihi- "tionbi the limits of the invention, reference being had te the-a pended claims 'ferthis Fig-Ishow-s diagrammatieeily ofieemboiiif-ment dime-invention; and r By Way- Ofexample theihventiiin isillustratediii cembinationwith an internal combiistiri engine of any silitable type,- which, as shown incli'icles a crank shaftl, Cylinders 2; end cam shit-ft 3 operatively edhhected to theerenkshfitl'hy means of-fa vertical shaft 4 ridsditaMegedri-fig 'A-i eservoir or mnk 5 provides a sdurce:oi lubricant supplyand is *prf'e'rfakily meunted 'en any suitabl -em t of the" engine --st1 pp01tiI-1g tfiieture. Lubrimit feed pump 7, preferably a gear pump of a suitable type, which pump feeds lubricant under pressure to the engine through feed conduit 8. A suitable circulating system, comprising a plurality of conduits 9 con nected with said feed line 8, conducts lubricant to the various moving parts of the mechanism to be lubricated, from which the lubricant drains into the crank-case 10 of the engine. A conduit 11 connects both ends of the crank-case with a suction or discharge pump 12, preferably of the gear type, which returns lubricant through a conduit 13 to the tank 5. A vent pipe 14 preferably connects said tank with the casing of the engine.

Pumps 7 and 12 may be suitably mounted in a pump unit 15 which is attached to the engine casing, and are preferably operatively connected as by means of suitable gearing with a shaft 16 geared to the crank shaft 1.

In order to prevent the pressure of the It.- bricant delivered to the mechanism'by the feed pump 7 from becoming too great, suitable means are provided whereby, above a certain pressure, a part of the lubricant is returned to the tank 5. In the form shown, said feed pump is connected by a conduit 17 with the return conduit 13, and a suitable valve 18 in said conduit is adapted to open when the pressure in the conduit 8 reaches a predetermined amount, said valve being preferably of a type more fully described hereinafter.

To prevent damage to the engine, in case of failure of the feed pump to deliver a proper supply of lubricant, the discharge pump 12 is adapted to return lubricant from the crank case to the mechanism to be lubricated instead of to the tank 5, and to this end is preferably connected by means of a suitable conduit with the feed line 8, said conduit having a valve therein adapted to open when the pressure of said discharge pump exceeds the pressure of said feed pump. In the form shown, the conduit 17 is employed for this purpose, and is provided with a valve which is adapted to open when the pressure in the conduit 13 reaches a predetermined point over that of conduit 8.

Fig. 2 shows one type of valve mechanism which may be employed for this purpose. The pressure relief valve 18 comprises a tubular valve member closed at one end and slidably mounted in a recess 19, formed in the pump unit 15, the conduit 17 being connected to one side of said recess. The outer end of said recess is closed by a plug 20 having threaded engagement 21 with the walls of said recess. Resilient means, such as a coil spring 22, are interposed between plug 20 and valve member 18 and normally maintain the latter in engagement with its seat 23. The tension of said spring maybe adjusted by turning plug 20, so that when the pressure in feed line 8 reaches a predetermined amount, valve 18 will be forced down in recess 19 and will uncover conduit 17, placing conduit 8 in communication with return conduit 13.

Within said tubular member 18 and concentrio therewith extends a post 24, mounted on the closed end of said member, and being hollow to slidably receive a valve stem 25 of a valve member 26. The latter is adapted to seat against the closed end of valve member mber 18 is in closed position. Lubricant under pressure from discharge pump 12 passes through conduit 17 and opening 32 to the interior of tubular member 18, and thence through ports 28 tends to open valve 26 against the pressure in feed line 8 and tension of spring 30. This tension may be adjusted by turning the nut 29.

The operation of the system will now be readily observed. During normal operation of the engine, lubricant is fed by feed pump 7 through the circulating system to the crankcase, and is returned by discharge pump 12 to the supply tank. When the pressure in the feed line reaches a predetermined amount, depending on the tension of spring 22, valve 18 is forced downward and part of the lubricant is fed by the feed pump through return pipe 13 to the supply tank, without passing through the discharge pump.

Now, with the engine cold and oil congealed in pipes 6 and 13, the engine is started and the pump 7 is ineffectual in drawing oil in any quantity from the tank 5. The pump 12, however, will immediately draw some oil from the crank-case, due to the short pipe connection and to the better protection of the crank-case oil, and this will create a high pressure on the outlet side of the pump 12 because of the resistance caused by the congealed oil in the pipe 13. There is then less pressure in the pipe 6 than in the pipe 13 and this will cause the valve 26 to be raised from its seat and oil will flow through the conduit .17, the ports 32 and 28 and into the conduit 8 by which it is carried to the various bearings of the engine. This'flow of oil will continue until the pump 7 begins to draw oil in quantity from the tank 5 and thereby create a pressure in the conduit 8 greater than that in the pipe 13, and at that time the valve 26 will automatically close and the system will operate in the normal manner described above. That is, the system will thereafter operate by the pump 12 withdrawing oil from the crankcase and delivering it to the tank 5, and the pump meats 1 7 will withdraw oil from the tank 5 and dej liver it to the engine bearings under pressure, the upper limit of which is determined by the by-pass valve 18.

The invention thus insures against failure of a proper supply of lubricant to the engine and prevents consequent damage. It is, more over, automatic in operation, simple and emcient, and economical to manufacture and install. It is to be expressly understood, how ever, that the invention is not limited to the embodiment illustrated, but is susceptible of a variety of expressions, and that changes may be made in the construction and arrangement of the parts without departing from the spirit of the invention. Reference is therefore to be had to the appended claims for a definition of the limits of the invention.

What is claimed is Y l. The combination with mechanism to be lubricated, of a lubricating system having a feed pump, a discharge pump, a conduit connecting the discharge sides of said pumps, and

pressure-operated means controlling the direction of flow in said conduit. 7

2. In an internal combustion engine, a lubricating system having a source of lubricant source to said engine, a positively actuated dischargmg means between the crankcase of said engine and said source of supply, a bypass connecting said pump with said discharging means, and a pressure relief valve in said by-pass opening toward the feed pump. 7 p a 3. The combination with mechanism to be lubricated and a source oflubricant supply, of conduits connecting said elements and constituting therewith a closed circulating system, feed and discharge pumps in said system, a conduit connecting the discharge sides of said pumps, anda pressure-operated valve in said conduit adapted to open when the differential of pressure between said pumps reaches a predetermined amount in either direction. i. The combination with mechanism to be lubricated and a source of lubricant supply,

said engine, a pump discharging lubricant from said engine to said source, and a pair of pressure-controlled valves interposed between said pumps, one of said valve being adaptedto open when the pressure of'said feeding pump exceeds a predetermined said discharging pump is greater thanthe 7 pressure of said feed pump by a predetermined amount.

6. In aninternalcombustion'engine, a'lu-' a conduit connecting said pumps, and a pressure-actuated valve in said conduit adapted to open when the pressure of said discharge pump exceeds the pressure of said feed pump by a predetermined amount.

p 8. In combination with mechanism to be lubricated and-a source of lubricant supply, conduits including feed and discharge pumps connecting said elements and forming'tlierewith a circulating system, and valve means supply, a pump feeding lubricant from said] between said pumps opened by back pressure created in a portion of said system by said discharge pump, V

9; In an'internal combustion engine, alubricating system having a source of lubric ant supply, a conduit connecting the'lat'ter with said engine and including a feed pump,

conduit connecting saidengine with said source of supply and lncluding a discharge pump, and pressure-operated valve means connecting said conduits and adapted to sup- "ply lubricant from said discharge pump to said engine, said means being actuated by back=pressure created by said discharge pump between the latter and said source of "S p y 10. In an-inte'r'nal combustionengine,the

combinationwith aclosed lubricant circulatingsystem having as'ource of supply, feeding means connecting said source with said engine, andpositively actuated discharging means connecting said engine with said source, of a-pressure-cont-rolled by-pass valve between said dlscharglng means and said engine, said valve being adapted to open when I lubricant in part of said system is congealed.

11. In an internal combustion engine, a lubricating system having a source of lubricant supply, means including feed and discharge pumps operatively connecting said source of supply with said engine and forming a closed circulating system, and a pair of normally closed valves interposed between said pumps, one of said valves being adapted to open when the differential pressure of said feed pump reaches a predetermined value over the discharge pump pressure and the other when the differential pressure of said discharge pump reaches a predetermined,

amount over the teed pump pressure.

12. In an internal combustion engine, a lubricating system comprising a source of lubricant supply, a conduit connecting the latter with said engine, said conduit including feed and discharge pumps for the circulation of lubricant, a. conduit connecting said pumps, a valve member in said conduit adapted to open when the differential pressure in one direction reaches a predetermined amount, and a second valve member forming part of said first-named valve member and adapted to open when the differential pressure in the opposite direction reaches a predetermined an ount.

13. In an internal combustion engine, a lubricating system comprising a source of lubricant supply, a conduit connecting the so latter with said engine, said conduit including a feed pump and a discharge pump for the circulation of lubricant, a conduit connecting said pumps, a valve in said conduit,

a second valve forming part of said firstnamed valve, and resilient means normally closing said valves, one of said valves being adapted to open when the pressure in one direction in said conduit exceeds the pressure in the other direction by a predetermined amount.

14. In an internal combustion engine, a lubricant circulating system including feed and discharge pumps, a source of lubricant supply, an external circuit connecting said supply and pumps, and means including a shunt circuit Within the body of the engine and connected to said discharge pump for supplying lubricant to the engine bearings.

15. In an internal combustion engine, a

source of lubricant supply, a supply pump for forcing lubricant to the engine from said supply, a discharge pump for forcing lubricant from said engine to said supply, a conduit connecting said pumps, and means controlled by the discharge of one of said pumps for controlling the flow of lubricant through said conduit.

In testimony whereof I have signed this specification.

5o LIONEL M. VVOOLSON.

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